퍼지 클러스터링 기반 신경회로망과 SVM 패턴 분류기 설계에 관한 연구 : 검은색 폐플라스틱 분류를 중심으로

배종수 수원대학교 2017 국내석사

Lately, the amount of waste plastics including black plastics is getting more and more increasing. According as lots of plastics are widely used in various industrial fields. Under these circumstances, necessity for recycling of limited useful resources is getting more and more important gradually and research related to plastic sorting system is being largely required for plastic recycling. Plastic sorting system constructed currently by Near Infrared Ray(NIR) is being exploited to classify colored plastics besides black plastic. However, the classification of black plastics still remains a challenging issue, because of the absorption of infrared rays of NIR spectrometer for black plastics. Design methodology to identify black plastics in introduced. ATR FT-IR, Raman, and LIBS spectroscopies are used to carry out qualitative as well as quantitative analysis and also comparative studies for black plastics. For ATR FT-IR spectrometer, the spectra data of black plastics can be measured through the contact of interval gap between the spectrometer and plastic. Its measurement speed is faster compared to NIR spectrometer. ATR FT-IR spectrometer which is the contact type of interval gap, has difficulty in the on-line application. As the contactless type of interval gap, Raman spectrometer can measure the samples quickly, but its ensuing effect leads to the difficulty of data extraction due to lots of noises as well as the difficulty of application to on-line system. Therefore, LIBS spectrometer which is the contactless type, is used to effectively extract spectra data being applied in the on-line system. But, whenever the spectra data are measured in the same sample through spectrometer, the position of peak points of the characteristic spectra data are partially changed or shifted. Design methodology which takes into consideration for the changed or shifted spectra data are introduce in this study. The design method of determining input variables corresponding to data peak points based on the chemical characteristic lead to more reasonable and effective technique for improving the performance of FRBFNN and SVM classifiers. Moreover, in order to improve the identification performance, intelligent computing algorithms such as Principal Component Analysis(PCA), Fuzzy Transform(FT), Fuzzy Radial Basis Function Neural Networks(FRBFNN), Support vector machine classifiers(SVM) and Particle Swarm Optimization(PSO) are considered to analyze and classify some types of black plastics. In the preprocessing step for classifying some black plastics, the characteristic peak points are extracted and region corresponding to each characteristic peak point is taken into consideration. Here, as the preprocessing techniques, PCA and Fuzzy Transform algorithms are used for the dimension reduction of data. And FRBFNN and SVM are exploited as intelligent classifiers. FRBFNN classifier is considered as the powerful tool with the synthesis technologies of fuzzy theory and neural networks for the identification of black plastics. SVM classifier is used for comparative studies with FRBFNN classifier. In conclusion, the design methodology related to preprocessing techniques based FRBFNN classifier is demonstrated as competitive and preferred network architecture, as well as superb performance.

Black Fungibility and the PosthuMan: Becoming Microbial Geographies

Rawson, Ariel The Ohio State University ProQuest Dissertations & 2021 해외박사(DDOD)

The microbiome—the collection of microbes in a habitat or body—is currently an object of interdisciplinary excitement. The connection to the Anthropocene is explicit: loss of microbial diversity is about an epoch of planetary loss, where the stakes for people and the environment are inseparable. The microbiome is central to a new, seemingly “post-racial” view of life that emphasizes the environmentally contingent distribution of microbes over genes and plasticity over fixity. Against this, I demonstrate how claims about microbes, contingency, and plasticity draw on and reproduce implicit racial assumptions. Drawing on scholarship on black fungibility, I show that these seemingly post-racial approaches take up civilizational tropes of race and nature in terms of narratives of both improvement and degeneration. Recent scholarship demonstrates that race re-emerges in microbiome science through the idea of the “noble savage,” whose “vanishing” “natural” microbiome is then subject to bioprospecting. I extend these critiques of microbiome science by also unpacking the racial distinction that emerges between the desire for the “regenerating” or “rewilded” gut and the anxiety around the “degenerating” gut. In my analysis, this microbial formation of civilizational crises figures culture-nature relations as degenerating, falling from an originary, “good,” prelapsarian condition of nature-culture entanglement. I show how this makes race an internal threat, as microbiome science focuses on the perils of “bad,” low socioeconomic status neighborhoods. In this view, environmental crisis becomes an urban-industrial threat, as racialized neighborhoods disrupt microbial ecologies and threaten human extinction. By using black fungibility as a central analytic, I critique the color line forged by both biocentric fetishization of indigeneity as wilderness and biocentric anxiety around the city and urban degeneration.

Studies on thermal treatments of various solid fuels and reduction of waste oil

박상신 Graduate School, Yonsei University 2015 국내박사

Recently, thermal treatments of various solid fuels such as refuse plastic fuel (RPF), coal, single base propellant, and waste tire have a special attention regarding economical and environmental aspects. The thermal treatments included various processes of pyrolysis, gasification, and combustion. One common way of waste disposal of RPF, expired single base propellant, and waste tire is pyrolysis for recycling resource and reduction of environmental pollution. On the other hands, gasification is the most common way and more efficient process for produced fuel gases of CO and H2 from fossil fuel such as coal. The pyrolysis occurs when oxidant is not supplied, while gasification occurs when insufficient oxidant is supplied; the amount of oxygen supplied for coal gasification is usually 1/3 to 1/5 of that supplied for complete combustion. However, the thermal treatment of various solid fuels necessarily generated waste oil such as tar, which can cause operational problems in many thermo-chemical conversion processes. Therefore, the waste oil disposal is important. Recent increases in fossil fuel costs have given renewed interest to applications of refuse plastic fuel (RPF) for heat and power generation. RPF contains 60%?70% waste plastics, which consists of 30%?35% polystyrene (PS), 20%?25% polyvinyl chloride (PVC), 5% low-density polyethylene (LDPE), and 5% polypropylene (PP). Product yields of liquid, solid, and gas were obtained from pyrolysis experiments on RPF using a tube furnace in a nitrogen atmosphere under three non-isothermal conditions (maximum temperature: 400°C, 600°C, and 800°C). And, the effect of the temperature on the product yields of liquid, solid, and gas were discussed. The gas compositions and liquid compounds were analyzed using gas chromatography (GC) and gas chromatography mass spectrum detector (GC-MSD), respectively. Using a thermo-gravimetric analysis (TGA) reactor, thermal decomposition characteristics of PS, PVC, LDPE, and PP as well as RPF during pyrolysis were analyzed. Using the single reaction model, the activation energy and pre-exponential factor for RPF pyrolysis were 211.11 (kJ/mole) and 9.04E+13 (l/min), respectively. Using the parallel reaction model, the activation energies of PS, PP, LDPE, PVC{1}, and PVC{2} (subscripts {1} and {2} refer to the first and second degradation of PVC in mass) were 231.83, 193.55, 175.92, 72.26, and 164.94 (kJ/mol), respectively, and their pre-exponential factors were 2.27E+17, 4.49E+13, 7.09E+11, 1.24E+06 and 2.16E+11 (l/min), respectively. Three-dimensional computational fluid dynamics (CFD) modeling of the gasification performance in a one-stage, entrained-bed coal gasifier (Shell Coal Gasification Process [SCGP] gasifier) was performed, for the first time. The parametric study used various O2/coal and steam/coal ratios, and the modeling used a commercial code, ANSYS FLUENT. CFD modeling was conducted by solving the steady-state Navier-Stokes and energy equations using the Eulerian-Lagrangian method. Gas-phase chemical reactions were solved with the Finite-Rate/Eddy-Dissipation Model. The CFD model was verified with actual operating data of Demkolec demo IGCC facility in Netherlands that used Drayton coal. For Illinois #6 coal, the CFD model was compared with ASPEN Plus results reported in National Energy Technology Laboratory (NETL). For design coal used in the SCGP gasifier in Korea, carbon conversion efficiency, cold gas efficiency, temperature, and species mole fractions at the gasifier exit were calculated and the results were compared with those obtained by using ASPEN Plus-Kinetic. The optimal O2/coal and steam/coal ratios were 0.7 and 0.05, respectively, for the selected operating conditions. The Republic of Korea has a plan to construct an incineration facility for expired propellant from munitions including 155 mm, 105 mm, and 8 inch howitzer shells. It is important to understand thermal characteristics of the propellant before designing the incineration facility. The ingredients of a propellant sample were analyzed using liquid chromatography-mass spectrometry, and the temporal mass loss of the sample was measured using thermo-gravimetric analysis (TGA) in an argon atmosphere up to a temperature of 350°C at different heating rates of 10°C/min, 20°C/min, and 30°C/min. The mass of the sample started decreasing at a temperature of about 180°C, and was fully decomposed when the temperature reached about 210°C. Using a first order model to described the reaction kinetics, we obtained a pre-exponential factor of 2.09×1039 [1/min] and an activation energy of 335.77 [kJ/mol] for the sample. In order to understand product gas compositions, another thermal decomposition experiment was carried out using a lab-scale tube furnace under an argon atmosphere to a temperature of 350°C. Gas compositions were analyzed using gas chromatography and gas detecting tubes. Residual ash compounds were analyzed using X-ray fluorescence. Amount of waste tire has been increased with automotive industry development. Disposal of the waste tire caused a huge environmental problem and an economic cost. Recently, the disposal by pyrolysis of waste tire has been studied by many researchers for recycling resource and reduction of environmental pollution. Product yields of liquid, solid and gas were investigated by pyrolysis experiments for scrap waste tire using a lab-scale tube furnace under nitrogen atmosphere for residence times of 5, 10, 20 and 30min and three isothermal conditions (maximum temperatures: 400°C, 600°C and 800°C). The gas compositions and liquid compounds were analyzed using gas chromatography (GC) and gas chromatography mass spectrum detector (GC-MSD), respectively. Structure of carbon produced at 1300°C was compared with commercial carbon black (CB) samples (N660 and ISAF) using a scanning electron microscope (SEM), transmission electron microscopes (TEM). The product yield of carbon was compared with experimental result and chemical equilibrium calculation result. A dielectric barrier discharge (DBD) reactor was fabricated and operated in two steps. In the first step (oil mist collection) oil mist aerosols were collected and in the second step (oil mist-to-gas conversion), without supplying oil mist particles but with supplying only clean air flow, collected oil mist particles were converted to gas species. An aerodynamic particle sizer, a scanning mobility particle sizer system, and a real-time gas analyzer were used to measure particle and gas concentrations at the inlet and outlet of the DBD reactor. The oil mist collection efficiency decreased from 78% to 21% but the oil mist-to-gas conversion efficiency increased from 6% to 95%, with increasing frequency from 1 kHz to 10 kHz. Low frequency caused higher amplitude of oscillating particle movement between the electrodes, resulting in higher collection efficiency. At a higher frequency, more electrons were generated, which resulted in the formation of more reactive oxygen species and thus increased subsequent oxidation. Increased surface temperature of the DBD reactor with higher frequency also contributed to higher oil mist-to-gas conversion efficiency. The DBD reactor can be applied to reduce oil mists generated in metal working and cooking processes. 폐 플라스틱 연료, 석탄, 수명도래 폐 추진제, 및 폐 타이어 등 다양한 고체연료들의 열적 처리는 경제적?환경적 측면에서 특별한 관심을 가지고 있다. 열적 처리의 다양한 공정은 열분해, 가스화, 연소 등으로 이루어져 있다. 폐 플라스틱 연료, 수명도래 폐 추진제, 및 폐타이어 등의 가장 일반적인 열적 처리는 열분해 이다. 반면에, 가스화는 석탄과 같은 화석연료 등을 이용하여 CO 및 H2와 같은 연료가스를 생산하는 가장 일반적인 방법이고 가장 효과적이다. 하지만, 다양한 고체연료들의 열적 처리는 필연적으로 타르와 같은 폐 오일을 입자 상태로 발생시킨다. 그러므로, 이러한 폐 오일 처리는 매우 중요하다. 최근 화석연료 가격의 증가 추세가 열 및 전기 생산을 위한 폐 플라스틱 재생 연료의 적용에 흥미를 유발 시킨다. 폐 플라스틱 재생연료는 30%?5% 폴리스타이렌 (PS), 20%?25% 폴리비닐 클로라이드 (PVC), 5% 저 밀도 폴리에틸렌 (LDPE), 5% 폴리프로필렌 (PP) 등 전체 구성의 60%?70%로 구성되어 있다. 온도 영향에 따른 고, 액, 기상 수율은 비등온 조건 (최대 온도: 400°C, 600°C, 및 800°C)에서 튜브 퍼니스를 이용하여 열분해 실험으로부터 얻어졌다. 열중량분석 반응기를 이용하여, 열분해 하는 동안 PS, PVC, LDPE, PP, 및 RPF의 열적 분해 특성은 분석되었다. 단일 반응 모델을 사용하여, RPF 열분해에 대한 활성화 에너지 및 전지수인자는 각각 211.11 (kJ/mole) 및 9.04E+13 (l/min)로 도출되었고, 평행 반응 모델을 이용하여, PS, PP, LDPE, PVC{1}, and PVC{2}의 활성화 에너지 값은 각각 231.83, 193.55, 175.92, 72.26, 164.94 (kJ/mol) 및 전지수인자는 각각 2.27E+17, 4.49E+13, 7.09E+11, 1.24E+06, 2.16E+11 (l/min)로 도출되었다. 1단 분류층 석탄 가스화기 (SCGP 가스화기)의 가스화 성능에 대한 3차원 전산수치해석이 최초로 수행되었다. 다양한 산소/석탄 비 및 스팀/석탄 비에 대한 매개변수 연구는 상용 코드인 ANSYS FLUEN를 사용하여 진행되었다. 전산수치해석은 Eulerian-Lagrangian 방법을 이용하여 steady-state Navier-Stokes 및 energy equations에 의해 계산되었으며, 가스상 화학 반응은 Finite-Rate/Eddy-Dissipation 모델을 적용하여 계산 되었다. 전산수치해석은 Drayton탄을 이용한 Demkolec demo IGCC 설비의 실제 운전결과로 검증되었다. Illinois #6탄에 대해, 전산수치해석은 NETL 보고서의 ASPEN Plus 결과와 비교?분석되었다. 한국의 SCGP 가스화기에 사용되는 설계 탄에 대해, 가스화기 출구에서의 탄소전환율, 냉가스 효율, 온도, 그리고 화학종의 함량은 ASPEN Plus-Kinetic을 이용하여 얻은 결과와 비교?분석되었다. 선택된 조건에 대해, 최적의 산소/석탄 및 스팀/석탄 비들은 각각 0.7 및 0.05 였다. 대한민국은 155 mm, 105 mm, 및 8 inch 곡사포로부터 수명도래 폐 추진제 (Single base propellant)에 대한 소각로를 건설할 계획에 있다. 소각설비 설계 전에 폐 추진제의 열적 분해 특성 데이터의 확보는 중요하다. 폐 추진제의 성상은 LC를 이용하여 분석되었고, 시간적 무게 감량은 열중량 분석 반응기를 이용하여 다양한 승온조건들 (10°C/min, 20°C/min, and 30°C/min)에 대해 측정되었다. 폐 추진제의 무게 감량은 약 180°C에서 시작되어 210°C에서 완전히 감량 되었다. 1차반응 모델 (Volume Reaction Model: VRM)을 이용하여, 폐 추진제에 대한 활성화 에너지 및 전지수인자는 각각 335.77[kJ/mol] 및 2.09E+37[1/min]로 도출되었다. 열적 분해시 발생하는 가스 성분을 측정하기 위해, 또 다른 열적 분해 실험을 무산소 분위기에서 수행되었다. 가스성분 분석은 GC 및 검지관 (NO, NO2)을 이용해 수행되었고, 잔류하는 회분은 XRF를 사용하였다. 폐 타이어의 양은 자동차 산업 발전과 함께 증가되고 있다. 폐 타이어의 처리는 막대한 환경 문제 및 경제적 비용을 야기 시킨다. 최근, 폐 타이어의 열분해 처리는 자원 재활용 및 환경오염 저감 측면에서 많은 연구자들에 의해 연구되고 있다. 고, 액, 기상의 발생 물질은 등온 조건 (최대 온도: 400°C, 600°C, 800°C) 및 체류시간 (5, 10, 20, 30분)에 대해 논의 되었다. 기상 성분 및 액상 성분은 각각 CG 및 CG-MSD에 의해 분석되었다. 1300°C에서 생산된 카본의 구조는 SEM 및 TEM 분석을 이용하여 상용 카본블랙 샘플들 (N660, ISAF)과 비교 되었다. 카본의 발생 수율은 실험결과와 화학평형계산 결과를 이용하여 비교?분석되었다. 유전체 베리어 방전 반응기는 본 연구를 위해 제작 되었고 2 단계로 실험되었다. 첫 번째 단계 (오일 미스트 집진)에서, 오일 미스트 입자는 유전체 베리어 방전 반응기 표면에 집진 되었고, 두 번째 단계 (오일 미스트 가스 변환)에서는 유전체 베리어 방전 반응기 표면에 집진된 오일 미스트가 가스로 변환되는 특성에 대해 실험이 진행되었다. 이러한 특성을 파악하기 위해, APS, SMPS, 실시간 가스분석기는 유전체 베리어 반전 반응기 전단과 후단에서 입자 및 가스 농도를 분석하였다. 증가되는 주파수 (1 kHz ~ 10 kHz)에 대해, 오일 미스트 집진 효율은 78%에서 21%로 감소하였고, 가스전환율은 6%에서 95%로 증가하였다. 유전체 베리어 방전 반응기의 표면 온도는 주파수가 증가할수록 함께 증가하였고, 이러한 현상은 가스전환효율의 증가에 기여했다.